Astronomers with the Lincoln Near-Earth Asteroid Research program spotted 25143 Itokawa on the 26th of September 1998. An earlier observation by the Sloan Digital Sky Survey had captured the same body just one week before this official discovery.
The Minor Planet Center officially published the name 25143 Itokawa on the 6th of August 2003 to honor Hideo Itokawa who lived from 1912 to 1999. He is widely regarded as the father of Japanese rocketry.
Itokawa orbits the Sun at a distance ranging from 0.95 to 1.70 AU every 18 months with an orbital period lasting exactly 557 days. The path has an eccentricity of 0.28 and an inclination of 2 degrees relative to the ecliptic.
The sample capsule returned to Earth and landed at Woomera, South Australia on the 13th of June 2010 around 13:51 UTC. Japan Aerospace Exploration Agency confirmed dust from the voyage originated from the asteroid on the 16th of November 2010.
Radar imaging by Goldstone in 2001 observed an ellipsoid shape measuring approximately 540 meters long and 290 meters wide. Scientists concluded that 25143 Itokawa is not a monolith but rather a rubble pile formed from fragments that have cohered over time due to its low density.